MORE PHOTOS: Several factors combined to produce spectacular sunset

FARGO - Eric DeBilt was out on his deck Sunday evening when the western sky lit up in a spectacular show as the sun set on the horizon.

The sky was aglow with orange and red hues mixed with purple – what used to be called a Kodak moment, back in the days of film.

These being the days of the smartphone, DeBilt reached for his iPhone and snapped a few pictures to preserve the moment.

So, as it turns out, did a lot of other people. The Forum received a gallery’s worth of photos from readers depicting the unusually vivid sunset.

As it happens, DeBilt was relaxing from unpacking after his recent move to a house on the northwest fringe of Mapleton, a location he specifically chose for the big sky view it afforded.

“Just happened to be at the right place at the right time,” he said.

At first, the sunset didn’t seem especially noteworthy, but the kaleidoscope of changing colors turned out to be truly memorable.

John Wheeler, WDAY’s chief meteorologist, received a number of inquiries from viewers wondering about the unusual sunset.

Several factors came together to produce Mother Nature’s light show, he said.

First, light rays in the blue spectrum, which prevail during midday, are not as evident early in the morning or late in the evening.

In the evening, with the sun at a lower angle, the longer wavelengths of the visible light spectrum – the orange and red hues – are more visible because the blue light is scattered, deflected from a direct path to the eyes.

The beauty can be enhanced, as it was Sunday night, when clouds reflect red sunlight, giving the clouds the same rich red visible along the horizon.

Sunday’s clouds had a lot of “structure,” likely including rain that hadn’t reached the ground, Wheeler said.

“Lots of times the undersides of clouds are flat and boring,” unlike Sunday, he said.

Wheeler had to study sunset photos sent in from viewers – he didn’t see the show because he was in the Twin Cities watching a Peter Frampton concert.